1. Field of the Invention
The present invention relates to a tow trailer for transporting cargo.
2. Description of the Prior Art
Cargo is often transported and stored on pallets or in large cargo or shipping containers. Pallets are typically of a standard construction having two flat wooden platforms with wooden spacers therebetween creating a gap of several inches. The forks of a forklift may be inserted into this gap to lift the pallet and any materials thereon. Material on pallets or in shipping containers is typically transported by loading a number of pallets onto a large flatbed truck using a forklift, driving the loaded truck to the point of destination, and unloading the pallet by forklift at the destination. This method of transport is efficient for large numbers of pallets, but requires forklifts at both the point of origin and the delivery point, and a flatbed truck for transporting the pallet.
A variety of applications exist for the economical transport of a single pallet of material. In the landscaping business, for example, sod is generally purchased by the pallet. Standard truck-and-forklift delivery methods are acceptable when the particular landscaping project requires a number of pallets of sod; however, many landscaping projects arise requiting only a single pallet of sod, or less. Because of the considerable expense involved, the transport of a single pallet of material is generally cost-prohibitive using existing transport methods.
For a variety of reasons, existing prior art devices capable of transporting a single pallet of material are less than entirely satisfactory. Many of these devices cannot comply with Department of Transportation ground clearance regulations (eleven (11) inches minimum) for load carrying. Other devices have a lifting platform pivotally connected behind its wheel assembly, resulting in an unstable towing configuration.
The device shown in U.S. Pat. No. 5,584,639 to Walker, Jr. solves many of the above problems and is incorporated in its entirety by reference herein. The weight of the load is centered over the wheels or slightly in front of the wheels for a safe and stable towing configuration. The device also provides adequate ground clearance during load carrying.
The '639 trailer, however, has a number of problems. The '639 trailer is rigid and gives the cargo a bumpy ride during transport. The '639 trailer also is not modular and cannot be readily disassembled. Once the '639 trailer is assembled, it is too big to be shipped with the rest of the cargo and too difficult to disassemble during field use. The '639 trailer cannot easily fit into cargo planes and shipping containers.
The '639 trailer cargo carrying capacity is not adjustable. The '639 trailer cannot carry a variety of sizes of pallets and shipping containers, especially tall cargo, and is limited to loads with short heights. Furthermore, the standard trailer hitch used on the '639 trailer cannot easily hook up to larger vehicles, such as a Humvee or larger cargo truck.
It would, therefore, be advantageous to have a modular tow trailer that can transport cargo at one location, then the tow trailer can be partially disassembled to a compact size and transported with the rest of the cargo to a second location. It would be further advantageous to have the partially disassembled tow trailer fit within a cargo container.
A further need exists for a modular tow trailer capable of transporting larger pallets or cargo without the need for forklifts or a large flatbed truck. Additionally, a need exists for a modular tow trailer capable of lifting a pallet of material a distance above the ground sufficient to comply with Department of Transportation ground clearance regulations without tilting the load so far beyond the horizontal position that the cargo falls off of the pallet. Moreover, a need exists for a modular tow trailer which allows the load to be centered over the wheels of the trailer or slightly forward of the wheels, such that the loaded device is stable when towed.